Current Electricity PYQs Set 14 (PDF)

Set 14 of 21 · Questions 391-420 of 612

In the print window choose “Save as PDF”. The file prints without a web address or date line.

Mere Teacher · Previous Year Questions NEET Physics · Current Electricity · Set 14 (Q391-420)
Scan or visit mereteacher.com for free PYQ practice, timed CBT tests, step-by-step solutions and BroBot AI. Answers and solutions are free with a sign-up.
391. $The four arms of a Wheatstone bridge have resistances as shown in the figure. A galvanometer of 15Ω resistance is connected across BD . Calculate the current through the galvanometer when a potential difference of 10 V is maintainedacross AC .$ (1) $2.44 μA$ (2) $2.44 mA$ (3) $4.87 mA$ (4) $4.87 μA$ 392. $A conducting wire of length 'l', area of cross-section A and electric resistivity ρ is connected between theterminals of a battery. A potential difference V is developed between its ends, causing an electric current. If the length of the wire of the same material is doubled and the area of cross-section is halved, the resultantcurrent would be:$ (1) $\frac{1}{4} \frac{VA}{ρl}$ (2) $\frac{3}{4} \frac{VA}{ρl}$ (3) $\frac{1}{4} \frac{ρl}{VA}$ (4) $4 \frac{VA}{ρl}$ 393. $In an ammeter, 5 % of the main current passes through the galvanometer. If resistance of the galvanometer is G, the resistance of ammeter will be:$ (1) $\frac{G}{20}$ (2) $\frac{G}{199}$ (3) $199 G$ (4) $200 G$ 394. $In the Wheatstone's network given, P = 10Ω, Q = 20Ω, R = 15Ω, S = 30Ω . The current passing through the battery (of negligible internal resistance) is$ (1) $0.36 A$ (2) $0$ (3) $0.18 A$ (4) $0.72 A$ 395. $A capacitor of 8 F is connected as shown. Charge on the plates of the capacitor$ (1) $32 C$ (2) $40 C$ (3) $0 C$ (4) $80 C$ 396. $For the network shown in the figure the value of the current i is$ (1) $\frac{9 V}{35}$ (2) $\frac{18 V}{5}$ (3) $\frac{5 V}{9}$ (4) $\frac{5 V}{18}$ 397. $Three resistors having resistances r_{1}, r_{2} and r_{3} are connected as shown in the given circuit. The ratio i_{3} / i_{1} of currents in terms of resistances used in the circuit is [NEET 2021]$ (1) $\frac{r _{1}}{r _{2} + r _{3}}$ (2) $\frac{r _{2}}{r _{2} + r _{3}}$ (3) $\frac{r _{1}}{r _{1} + r _{2}}$ (4) $\frac{r _{2}}{r _{1} + r _{3}}$ 398. $The Wheatstone bridge shown in the diagram is balanced. If P_{3} is the power dissipated by R_{3} and P_{1} is the power dissipated by R_{1}, then the ratio \frac{P _{3}}{P _{1}} is$ (1) $\frac{K}{L}$ (2) $\frac{K ^{2}}{L}$ (3) $\frac{L}{K ^{2}}$ (4) $\frac{L}{K}$ 399. $A student measures the terminal potential difference (V) of a cell (of emf ϵ and internal resistance r) as a function of the current (I) flowing through it. The slope, and intercept, of the graph between V and I, then, respectively, equal$ (1) $- r and ϵ$ (2) $r and - ϵ$ (3) $- ϵ and r$ (4) $ϵ and - r$ 400. $In the given circuit, an ideal voltmeter connected across the 10Ω resistance reads 2 V . The internal resistance r, of each cell is$ (1) $1Ω$ (2) $0.5Ω$ (3) $1.5Ω$ (4) $0Ω$ 401. $In this figure the resistance of the coil of galvanometer G is 2 Ω . The emf of the cell is 4 V. The ratio of potential difference across C_{1} and C_{2} is$ (1) $1$ (2) $\frac{4}{5}$ (3) $\frac{5}{4}$ (4) $\frac{3}{4}$ 402. $In the given figure, there is a circuit of potentiometer of length AB = 10m. The resistance per unit length is 0.1Ω per cm. Across AB, battery of emf E and internal resistance 'r' is connected. The maximum value of emf measured by this potentiometer is:$ (1) $5V$ (2) $2.25V$ (3) $6V$ (4) $2.75V$ 403. $In the given circuit the internal resistance of the 18 V cell is negligible. If R_{1} = 400Ω, R_{3} = 100Ω and R_{4} = 500Ω and the reading of an ideal voltmeter across R_{4} is 5 V, then the value of R_{2} will be:$ (1) $300Ω$ (2) $450Ω$ (3) $550Ω$ (4) $230Ω$ 404. $In the given circuit, the current I through the battery will be$ (1) $2 5 A$ (2) $1A$ (3) $2 A$ (4) $1.5 A$ 405. $In a meter bridge experiment, the circuit diagram and the corresponding observation table are shown in figure. SI. NO. R 1 (cm) 1100060210013310 1.5 41 1.0 Which of the reading is consistent?$ (1) $3$ (2) $2$ (3) $4$ (4) $1$ 406. $When the switch S, in the circuit shown, is closed then the valued of current i will be:$ (1) $3 A$ (2) $5 A$ (3) $4 A$ (4) $2 A$ 407. $Each resistance in the given cubical network has resistance of 1Ω and equivalent resistance between A and B is$ (1) $\frac{5}{12} Ω$ (2) $\frac{12}{5} Ω$ (3) $\frac{5}{6} Ω$ (4) $\frac{6}{5} Ω$ 408. $A potentiometer wire of length 200 cm has a resistance of 20Ω . It is connected in series with a resistance of 10Ω and an accumulator of emf 6 V having negligible internal resistance. A source of 2.4 V is. balanced against a length L of the potentiometer wire. The value of L is$ (1) $100 cm$ (2) $120 cm$ (3) $110 cm$ (4) $140 cm .$ 409. $Two electric bulbs marked 25W - 220V and 100W - 220 V are connected in series to a 440 V supply. Which of the bulbs will fuse?$ (1) $both$ (2) $100W$ (3) $25W$ (4) $neither$ 410. $In a Wheatstone bridge (see fig.), Resistances P and Q are approximately equal. When R = 400Ω, the bridge is balanced. On interchanging P and Q, the value of R, for balance, is 405Ω . The value of X is close to:$ (1) $401.5 ohm$ (2) $404.5 ohm$ (3) $403.5 ohm$ (4) $402.5 ohm$ 411. $In the given electrical circuit, which one of the following equation is a correct equation?$ (1) $E_{2} - i_{2} r_{2} - E_{1} - i_{1} r_{1} = 0$ (2) $E_{1} - (i_{1} + i_{2}) R + i_{1} r_{1} = 0$ (3) $E_{1} - (i_{1} + i_{2}) R - i_{1} r_{1} = 0$ (4) $- E_{2} - (i_{1} + i_{2}) R + i_{2} r_{2} = 0$ 412. $In the given figure, a battery of emf E is connected across a conductor PQ of length ' l' and different area of cross-sections having radii r_{1} and r_{2} (r_{2} < r_{1}) Choose the correct option as one moves from P to Q:$ (1) $Drift velocity of electron increases.$ (2) $Electric field decreases.$ (3) $Electron current decreases.$ (4) $All of these$ 413. $In the given circuit, the current in resistance R_{3} is:$ (1) $1 A$ (2) $1.5 A$ (3) $2 A$ (4) $2.5 A$ 414. $In the circuit given below, if the bulb is to glow with maximum intensity, the value of ' R' is (neglect internal resistance of the cell)$ (1) $1.25Ω$ (2) $4.5Ω$ (3) $6Ω$ (4) $8.5Ω$ 415. $The equivalent resistance between A and B as shown in figure is:$ (1) $10k Ω$ (2) $5k Ω$ (3) $20k Ω$ (4) $30 k Ω$ 416. $The equivalent resistance between the points A and B in the following circuit is$ (1) $0.5Ω$ (2) $5.5Ω$ (3) $0.05Ω$ (4) $5Ω$ 417. $The current in 1Ω resistor in the following circuit is$ (1) $1 A$ (2) $0.5 A$ (3) $1.1 A$ (4) $0.8 A$ 418. $A Wheatstone bridge is used to determine the value of unknown resistance X by adjusting the variable resistance Y as shown in the figure. For the most precise measurement of X, the resistances P and Q [NEET 2022]$ (1) $should be approximately equal and are small$ (2) $should be very large and unequal$ (3) $do not play any significant role$ (4) $should be approximately equal to, 2X$ 419. $Two sources of equal emfs are connected in series. This combination is connected to an external resistance R. The internal resistances of the two sources are r_{1} and r_{2} (r_{1} > r_{2}). If the potential difference across the source of internal resistance r_{1} is zero then the value of R will be$ (1) $r_{1} - r_{2}$ (2) $\frac{r _{1} r _{2}}{r _{1} + r _{2}}$ (3) $\frac{r _{1} + r _{2}}{2}$ (4) $r_{2} - r_{1}$ 420. $Find the current in the three resistors as shown in the following figure?$ (1) $i_{1} = 0, i_{2} = \frac{4 V}{R}, i_{3} = \frac{2 V}{R}$ (2) $i_{1} = 0, i_{2} = 0, i_{3} = 0$ (3) $i_{1} = 0, i_{2} = \frac{2 V}{R}, i_{3} = \frac{4 V}{R}$ (4) $i_{1} = 0, i_{2} = \frac{2 V}{R}, i_{3} = \frac{2 V}{R}$